/*=========================================================================

  Library:   HMP

  Copyright (c) Kitware Inc.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0.txt

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

=========================================================================*/

// Qt includes
#include <QDebug>

// HMP includes
#include "LinearValueProxy.h"

// STD includes
#include <limits>

// --------------------------------------------------------------------------
// LinearValueProxyPrivate

class HCORESHARED_EXPORT LinearValueProxyPrivate
{
  Q_DECLARE_PUBLIC(LinearValueProxy);

protected:
  LinearValueProxy* q_ptr;
public:
  LinearValueProxyPrivate(LinearValueProxy& object);
  ~LinearValueProxyPrivate();

  bool isCoefficientValid() const;

  double Coefficient;
  double Offset;
};

// --------------------------------------------------------------------------
// LinearValueProxyPrivate methods

// --------------------------------------------------------------------------
LinearValueProxyPrivate::LinearValueProxyPrivate(LinearValueProxy& object)
  :q_ptr(&object)
{
  this->Coefficient = 1.0;
  this->Offset = 0.0;
}

// --------------------------------------------------------------------------
LinearValueProxyPrivate::~LinearValueProxyPrivate()
{
}

// --------------------------------------------------------------------------
bool LinearValueProxyPrivate::isCoefficientValid() const
{
  return qAbs(this->Coefficient) > std::numeric_limits<double>::epsilon();
}

// --------------------------------------------------------------------------
// LinearValueProxy methods

// --------------------------------------------------------------------------
LinearValueProxy::LinearValueProxy(QObject* _parent)
  : Superclass(_parent)
  , d_ptr(new LinearValueProxyPrivate(*this))
{
}

// --------------------------------------------------------------------------
LinearValueProxy::~LinearValueProxy()
{
}

// --------------------------------------------------------------------------
double LinearValueProxy::proxyValueFromValue(double value) const
{
  return (this->coefficient() * value) + this->offset();
}

// --------------------------------------------------------------------------
double LinearValueProxy::valueFromProxyValue(double proxyValue) const
{
  return (proxyValue - this->offset()) / this->coefficient();
}

// --------------------------------------------------------------------------
HMP_GET_CPP(LinearValueProxy, double, coefficient, Coefficient);
HMP_GET_CPP(LinearValueProxy, double, offset, Offset);

// --------------------------------------------------------------------------
void LinearValueProxy::setCoefficient(double newCoeff)
{
  Q_D(LinearValueProxy);
  if (d->Coefficient == newCoeff)
    {
    return;
    }
  emit proxyAboutToBeModified();
  d->Coefficient = newCoeff;
  this->updateProxyValue();
  emit proxyModified();
}

// --------------------------------------------------------------------------
void LinearValueProxy::setOffset(double newOffset)
{
  Q_D(LinearValueProxy);
  if (d->Offset == newOffset)
    {
    return;
    }
  emit proxyAboutToBeModified();
  d->Offset = newOffset;
  this->updateProxyValue();
  emit proxyModified();
}
